ITIN: A Practical Step-by-Step Application Guide
What an ITIN is, who needs one, how to apply, and how long the IRS currently takes, based on verified official information.
If you will have tax obligations in the United States and cannot obtain a Social Security Number (SSN), the number you need is called an ITIN. It is one of the areas that raises the most questions, so here is a clear breakdown based on the information the IRS currently publishes.
What an ITIN is and what it is used for
An ITIN (Individual Taxpayer Identification Number) is a tax identification number issued by the IRS to individuals who must file or report something in the United States and are not eligible for an SSN.
It is used to comply with the US tax system. It is not a work permit, it does not provide immigration status, and it does not replace an SSN. It is also not the same as an EIN, which identifies a business, not an individual.
Who needs one
The most common cases among Spanish-speaking founders are:
- Nonresident owners of a US company who must file or receive tax documents in the United States.
- Individuals who receive US-source income subject to withholding or reporting.
- Dependents or spouses who must be included on a federal tax return.
If your situation does not clearly fit one of these cases, the practical rule is simple: you apply for an ITIN when a specific tax obligation requires one, not "just in case."
How to apply: Form W-7
You apply using Form W-7. As a general rule, it must be submitted with a valid federal income tax return that establishes the reason for the application, unless one of the exceptions expressly recognized by the IRS applies to you (for example, certain withholding or third-party reporting situations).
In addition to the W-7, you need documents that prove your identity and foreign status. The IRS requires original documents or copies certified by the issuing agency; regular photocopies and notarized documents are not accepted.
How you can submit it
The IRS currently provides two options: by mail or in person.
By mail
You send the complete package (W-7, tax return if applicable, and documentation) to the IRS. It is the simplest option logistically, but it also means parting with original documents if you do not use certified copies.
In person
- IRS Taxpayer Assistance Center offering ITIN services: free, reviews your W-7, and authenticates most documents.
- VITA sites offering ITIN services: free, with limited availability and only in the United States.
- Certifying Acceptance Agent (CAA): an authorized paid agent. Reviews the W-7, helps complete it, and authenticates most documents, with limitations depending on the document and applicant. A CAA cannot authenticate foreign military identification cards; for dependents, a CAA can only authenticate passports and birth certificates. Documents the CAA cannot authenticate must be submitted with the application. CAAs operate both inside and outside the United States.
- Acceptance Agent (AA): also authorized and paid, reviews and helps complete the W-7, but does not authenticate documents. That is the key difference compared with a CAA.
You can compare the options in the IRS comparison table.
How long it takes
The IRS asks you to allow 7 weeks to receive notification about the status of your application. That timeframe increases to 9-11 weeks if you apply during peak tax filing season (January 15 through April 30) or from outside the United States.
These are IRS estimates, not commitments. No one—neither Maera nor any agent—can guarantee an issuance date or the approval of an ITIN.
Mistakes that delay the process
- Submitting the W-7 without the federal tax return when no exception applies.
- Including regular photocopies instead of originals or certified copies.
- Inconsistencies between the name on the passport and the name on other documents.
- Incomplete information in the reason for applying (the box explaining why you need the ITIN).
How this fits into your operations
If you are setting up your structure in the United States, the order matters: first understand what an LLC is and how it is taxed, then obtain the company’s EIN and, if your situation requires it, your personal ITIN. These are different identifiers and processes; confirm which ones apply to your situation.
Disclaimer. Maera is an administrative service: we support you with the operational and documentation side of the process. We are not a law firm or accounting firm, and this article provides general information, not legal or tax advice for your specific situation. Before making a decision, check the official sources linked above and, if your situation requires it, consult a professional in your country.
Frequently asked questions
Does an ITIN authorize me to work in the United States?
No. An ITIN only serves as a tax identification number before the IRS for certain individuals who have a U.S. tax obligation and are not eligible to obtain an SSN. According to the IRS, it does not authorize employment, change immigration status, provide access to Social Security benefits, or replace employment authorization. Its use must be tied to a specific tax purpose, such as filing a tax return, being listed on certain tax documents, or claiming an allowable exception for Form W-7.
Can I apply for an ITIN without filing a tax return?
Yes, but only if you qualify for an exception established by the IRS. The general rule requires filing Form W-7 together with a valid federal income tax return. The exceptions cover certain documented circumstances, such as specific withholding requirements, income subject to third-party reporting, or specific tax benefits; simply wanting the number for a bank account or an LLC is not sufficient. You must attach the documentation required for the specific exception. Under both the general process and an exception, the IRS requires originals or copies certified by the issuing agency, not ordinary photocopies or notarized copies.
What is the difference between an Acceptance Agent and a Certifying Acceptance Agent?
A Certifying Acceptance Agent, or CAA, can authenticate most identity documents for Form W-7, while an Acceptance Agent, or AA, cannot authenticate them. Both can review the application and submit it to the IRS, but using an AA generally requires providing originals or copies certified by the issuing agency. A CAA has limitations: it cannot authenticate foreign military identification cards and, for dependents, it can authenticate only passports and birth certificates. You can also visit a Taxpayer Assistance Center that provides ITIN services. The IRS compares these options and publishes the list of authorized agents. Before filing, confirm which documents your applicant will need to submit physically.
How long does it take the IRS to respond?
The estimated timeframe is seven weeks, or nine to eleven weeks if you file between January 15 and April 30 or from outside the United States. These are the processing times published by the IRS for ITIN applications, not a guarantee of approval or delivery by a specific date. Errors on Form W-7, a missing tax return when one was required, or documents that are neither originals nor copies certified by the issuing agency may extend the review. You should begin following up once the timeframe applicable to your filing method and season has elapsed.
Do I need an ITIN if my LLC already has an EIN?
Not necessarily: an EIN identifies the LLC, while an ITIN identifies an individual. An ITIN is appropriate only if there is a personal tax obligation that requires it. An EIN is requested using Form SS-4; if the business does not have its principal place of business in the United States, it cannot use the online application. The IRS accepts applications by fax at 304-707-9471, by mail at “Internal Revenue Service, Attn: EIN International Operation, Cincinnati, OH 45999,” or by phone at 267-941-1099 for authorized international applicants. On line 7b, “Foreign” or “N/A” may be entered when the responsible party does not have and is not eligible for an SSN or ITIN, in accordance with the Form SS-4 instructions. Neither of these numbers guarantees access to banking or payment services.